1. Field of the Invention
The present invention relates to a video image projection apparatus, a video image projection method, and a storage medium, and particularly to those suitable for use for projection of a video image.
2. Description of the Related Art
Video image projection apparatuses are capable of projecting images on a wall of a meeting room or the like even in an environment where a projection screen is not available. Therefore, using a video image projection apparatus, images projected on an area other than a projection screen can be viewed. Viewing images projected on an area other than a projection screen in this manner is becoming a common use case of video image projection apparatuses.
However, unlike dedicated projection screens, walls do not always have a flat projection area without a joint seam. For example, let it assumed that a wall is formed by plasterboards placed and fixed side by side. On this wall, the joints between the plasterboards form gaps. Therefore, there is a problem that if a character in an image is projected on such a joint area, the projected character is hard to be recognized.
To deal with this problem, Japanese Patent Application Laid-Open No. 2011-50013 and Japanese Patent Application Laid-Open No. 2013-64827 describe that an area where a projected image becomes missing is detected and the image is divided or reduced in size so as to avoid the area.
However, in the technologies described in the foregoing two laid-open patent applications, all input images are divided about an area unsuitable for projection and are then projected. Therefore, the technologies have a drawback that, if a to-be-divided region of an image contains a character, the projected character will be divided into left and right portions or upper and lower portions on opposite sides of an area unsuitable for projection. A similar drawback also occurs in the case where a dividing region of an image has a certain object other than characters.